A method of forming a polarizing film by adsorbing and orienting a dichroic material to a polyvinylalcohol-based resin (hereinafter, referred to as “PVA resin”) is well known. A representative use for a polarizing film is a display device such as a liquid crystal display (LCD). For example, a PVA resin-based polarizing film having a thickness of approximately 60 to 80 μm is attached to both surfaces of a liquid crystal panels of an LCD.
A PVA resin is hydrophilic, and thus a polarizing film is sensitive to change in temperature or humidity, easy to be elongated or contracted, and easy to have a failure such as curling. Accordingly, to inhibit elongation and contraction and reduce effects of a temperature and a humidity, a protective film is generally adhered to both surfaces of the PVA resin polarizing film. However, when the polarizing film has a large thickness, elongation and contraction are difficult to be inhibited, a stress is generated when the polarizing film is adhered to a liquid crystal panel, and staining on a display may be generated. In addition, recently, there is an increasing demand for a thin device or a device consuming low energy, and a demand for a thin polarizing film is also increasing.
For example, a process of forming a thin polarizing film is disclosed in the patent document 1.